Participants in this research project may have a disorder called deLange Syndrome (also known as Cornelia deLange or Brachmann-deLange, BDLS), or a genetic abnormality with features similar to BDLS. The purpose of this study is to learn about the molecular and genetic mechanisms underlying BDLS. In particular, we want to study what happens to cells from BDLS patients when they divide. We will culture and study blood cells and/or skin cells taken from participants in the laboratory to see if there is any abnormality. Genetic material will be extracted from the cells and the DNA analysed for genetic changes that might be associated with BDLS. The knowledge gained from these studies may allow doctors to diagnose BDLS more accurately, and to give families with the disorder better genetic counseling. Understanding the cause of BDLS may eventually lead to a treatment for BDLS or for other medical conditions.